diff options
Diffstat (limited to 'arch/x86/kernel/head64.c')
| -rw-r--r-- | arch/x86/kernel/head64.c | 81 |
1 files changed, 73 insertions, 8 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 7ba5d819ebe3..0c855deee165 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -32,6 +32,11 @@ #include <asm/microcode.h> #include <asm/kasan.h> +#ifdef CONFIG_X86_5LEVEL +#undef pgtable_l5_enabled +#define pgtable_l5_enabled __pgtable_l5_enabled +#endif + /* * Manage page tables very early on. */ @@ -39,6 +44,24 @@ extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD]; static unsigned int __initdata next_early_pgt; pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); +#ifdef CONFIG_X86_5LEVEL +unsigned int __pgtable_l5_enabled __ro_after_init; +EXPORT_SYMBOL(__pgtable_l5_enabled); +unsigned int pgdir_shift __ro_after_init = 39; +EXPORT_SYMBOL(pgdir_shift); +unsigned int ptrs_per_p4d __ro_after_init = 1; +EXPORT_SYMBOL(ptrs_per_p4d); +#endif + +#ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT +unsigned long page_offset_base __ro_after_init = __PAGE_OFFSET_BASE_L4; +EXPORT_SYMBOL(page_offset_base); +unsigned long vmalloc_base __ro_after_init = __VMALLOC_BASE_L4; +EXPORT_SYMBOL(vmalloc_base); +unsigned long vmemmap_base __ro_after_init = __VMEMMAP_BASE_L4; +EXPORT_SYMBOL(vmemmap_base); +#endif + #define __head __section(.head.text) static void __head *fixup_pointer(void *ptr, unsigned long physaddr) @@ -46,6 +69,41 @@ static void __head *fixup_pointer(void *ptr, unsigned long physaddr) return ptr - (void *)_text + (void *)physaddr; } +static unsigned long __head *fixup_long(void *ptr, unsigned long physaddr) +{ + return fixup_pointer(ptr, physaddr); +} + +#ifdef CONFIG_X86_5LEVEL +static unsigned int __head *fixup_int(void *ptr, unsigned long physaddr) +{ + return fixup_pointer(ptr, physaddr); +} + +static bool __head check_la57_support(unsigned long physaddr) +{ + if (native_cpuid_eax(0) < 7) + return false; + + if (!(native_cpuid_ecx(7) & (1 << (X86_FEATURE_LA57 & 31)))) + return false; + + *fixup_int(&pgtable_l5_enabled, physaddr) = 1; + *fixup_int(&pgdir_shift, physaddr) = 48; + *fixup_int(&ptrs_per_p4d, physaddr) = 512; + *fixup_long(&page_offset_base, physaddr) = __PAGE_OFFSET_BASE_L5; + *fixup_long(&vmalloc_base, physaddr) = __VMALLOC_BASE_L5; + *fixup_long(&vmemmap_base, physaddr) = __VMEMMAP_BASE_L5; + + return true; +} +#else +static bool __head check_la57_support(unsigned long physaddr) +{ + return false; +} +#endif + unsigned long __head __startup_64(unsigned long physaddr, struct boot_params *bp) { @@ -55,9 +113,12 @@ unsigned long __head __startup_64(unsigned long physaddr, p4dval_t *p4d; pudval_t *pud; pmdval_t *pmd, pmd_entry; + bool la57; int i; unsigned int *next_pgt_ptr; + la57 = check_la57_support(physaddr); + /* Is the address too large? */ if (physaddr >> MAX_PHYSMEM_BITS) for (;;); @@ -81,9 +142,14 @@ unsigned long __head __startup_64(unsigned long physaddr, /* Fixup the physical addresses in the page table */ pgd = fixup_pointer(&early_top_pgt, physaddr); - pgd[pgd_index(__START_KERNEL_map)] += load_delta; - - if (IS_ENABLED(CONFIG_X86_5LEVEL)) { + p = pgd + pgd_index(__START_KERNEL_map); + if (la57) + *p = (unsigned long)level4_kernel_pgt; + else + *p = (unsigned long)level3_kernel_pgt; + *p += _PAGE_TABLE_NOENC - __START_KERNEL_map + load_delta; + + if (la57) { p4d = fixup_pointer(&level4_kernel_pgt, physaddr); p4d[511] += load_delta; } @@ -108,7 +174,7 @@ unsigned long __head __startup_64(unsigned long physaddr, pgtable_flags = _KERNPG_TABLE_NOENC + sme_get_me_mask(); - if (IS_ENABLED(CONFIG_X86_5LEVEL)) { + if (la57) { p4d = fixup_pointer(early_dynamic_pgts[next_early_pgt++], physaddr); i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD; @@ -154,8 +220,7 @@ unsigned long __head __startup_64(unsigned long physaddr, * Fixup phys_base - remove the memory encryption mask to obtain * the true physical address. */ - p = fixup_pointer(&phys_base, physaddr); - *p += load_delta - sme_get_me_mask(); + *fixup_long(&phys_base, physaddr) += load_delta - sme_get_me_mask(); /* Encrypt the kernel and related (if SME is active) */ sme_encrypt_kernel(bp); @@ -206,7 +271,7 @@ again: * critical -- __PAGE_OFFSET would point us back into the dynamic * range and we might end up looping forever... */ - if (!IS_ENABLED(CONFIG_X86_5LEVEL)) + if (!pgtable_l5_enabled) p4d_p = pgd_p; else if (pgd) p4d_p = (p4dval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base); @@ -322,7 +387,7 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data) BUILD_BUG_ON((__START_KERNEL_map & ~PMD_MASK) != 0); BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0); BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL)); - BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == + MAYBE_BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == (__START_KERNEL & PGDIR_MASK))); BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END); |